These helpful tips will let you know when to harvest melons from the vine.
Picking a Vine-Ripe Melon
Gauging when melons are at the peak of flavor can be tricky, especially with watermelons. Watch for the following signs:
Watermelons. Watch the tendril closest to the melon stem. When it turns brown and dries up, the melon usually is ripe. With some watermelon varieties, however, the tendril dries and drops off more than a week before the melon is fully ripe, so use other methods, too. Monitor the melon's weight. Lift it daily. As it approaches maturity, weight increases. The surest sign of ripeness for most watermelons is the color of the bottom spot where the melon sits on the ground. As the watermelon matures, the spot turns from almost white to a rich yellow. Also, all watermelons lose the powdery or slick appearance on their top and take on a dull look when fully ripe.
Cantaloupes. Look for a crack on the stem where it meets the fruit. Give a gentle tug, and if the melon separates easily, it's probably ripe. If not, let it sit at room temperature a day or two. Gauge its ripeness then by aroma and softness of the blossom end of the melon.
Others (honeydew, Charentals, Crenshaw, winter). Watch for skin color changes. Some varieties go from dull gray to bright yellow when fully ripe. Aroma is a good indicator, too, along with softness at the blossom end. Look for full slip (crack on the stem that goes all the way around). Winter melons, which have hard rinds and which can be stored, should be left on the vine as long as possible. Check periodically for fine cracks in their rinds which indicate ripeness.
Read more about early melon varieties: A Guide to Early Melon Varieties.